Abstract: Techniques are described that allow a network device, such as a router, to dynamically build VLAN interfaces based on subscriber information strings included within packets. In particular, the network device comprises an interface controller and a forwarding controller, where the forwarding controller receives the packet over an Ethernet port and forwards the received packet to the interface controller. The packet includes both Ethernet tagging information and a subscriber information string. The interface controller comprises an Ethernet module that dynamically builds a primary virtual local area network (VLAN) sub-interface (PVS) based on the Ethernet tagging information. The Ethernet module also dynamically builds a subscriber VLAN sub-interface (SVS) based on the subscriber information string. The SVS allows the network device to distinguish between subscribers residing on the same VLAN, and, therefore, to provide subscriber specific services.